1. Field of the Invention
The present invention relates to a nematocide for controlling nematode in soil to prevent nematode.
2. Description of the Prior Art
It has been important to control soil pests, for perennial crops such as fruit trees and tea tree. Recently, a concentrated utilization of up-lands, a greenhouse culture and a special production of vegetables have been developed to cause an injury by continuous cropping caused by soil nematode and disease germs. In an up-land which is not suitable for culturing crop plants, it has been known that soil nematode affect to the troubles.
The damages caused by the soil nematode are found in various forms and are usually a poor initial growth, a death and a reduction of yield caused by the poor growth or the death. In the case of a root crop plants, the soil nematode remarkably damage a market value of root crops by a deformation or a surface damage. Once, a damage caused by nematode is given in an up-land, it is impossible to attain a continuous cropping. It is not easy to consider a rotation cropping system under a concentrated agriculture system. Therefore, it has been required to find a safety economical nematocide which can be easily applied.
The known nematocides are mainly halogenohydrocarbon fumigants such as chloropicrin, methyl bromide, D-D(1,3-dichloropropene), EDB(ethylene dibromide), DCIP(bischloroisopropyl ether) and DBCP(1,2-dibromo-3-chloropropane) etc.
These nematocides are not easily used in view of a mucous stimulation and a metal corrosion. Although phytotoxicity is not found by using DBCP and DCIP, serious phytotoxicity is caused by using the other nematocides. Most of the nematocides are used in liquid forms, and accordingly, it is necessary to provide a water-seal of a soil surface for a while or to cover with a polyethylene film in order to impart the nematocidal effect and it is also necessary to discharge the nematocide in the atmosphere by a cultivation for a gas discharge after the treatment in the soil treatment. Thus, remarkable inconvenience is caused in the processing. DBCP can be granulated, however, the production of DBCP is inhibited in view of toxicity to human-body and a long residue of DBCP in a soil and underground water. DCIP has a low nematocidal effect.
In USA, certain contact nematocides as organophosphorus agents such as Fensulfothion (O,O-diethyl-O-(4-methylsufynyl)phenylphosphorothioate), Ethoprop(O-ethyl S,S-dipropylphosphorodithioate) and Phenamiphos[ethyl 3-methyl-4-(methylthio)phenyl(1-methylethyl)phosphoroamidate]; and carbamate agents such as Carbofuran (2,3-dihydro-2,2-dimethyl-7-benzofuranyl methyl carbamate), and Aldicarb[2-methyl-2-(methylthio)propionaldehyde O-(methylcarbomoyl)oxime] have been used.
These contact namatocides have remarkable toxicity and can be used in a form of granule only by a special expert.
The following nematode diseases have been known. Leaf nematode disease (Aphelenchoides ritzema-bosi. Aphelenchoides fragariae); Stem and bulb namatode disease (Ditylenchus dipsaci); Root knot nematode disease (Meloidogyne incognita var. acrita) and Meloidogyne hapla); Stem nematode disease (Ditylenchus dipsaci); Root lesion nematode disease (Pratylenchus coffcae, Pratylenchus penetraus); Cyst namatode disease (Heterodera glycines and Globodera rostochiensis).